package Thread0903;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * 线程池是线程管理机制
 * 1.为了重复使用线程
 * 控制线程数量，避免资源消耗
 */

public class ThreadPoolDemo {
    public static void main(String[] args) {
        ExecutorService threadPool= Executors.newFixedThreadPool(3);
        for (int i=0;i<5;i++){
            Runnable r=new Runnable() {
                @Override
                public void run() {
                    try {
                        Thread t=Thread.currentThread();
                        System.out.println(t.getName()+":正在执行一个任务");
                        Thread.sleep(5000);
                        System.out.println(t.getName()+"：执行任务完毕");
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            };
            threadPool.execute(r);
            System.out.println("将一个任务交给了线程池");
        }

//        threadPool.shutdown();
        threadPool.shutdownNow();

        System.out.println("系统停止线程");
    }
}
